JP2002299725A - Magnetoresistive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of the conventional element, that hot electrons which go over a tunnel layer are necessary to ballistically transmit at least four layers or more of non-magnetic or magnetic layer comprising a base part, so that the gain of an emitter current to a collector current becomes degraded to a very poor level. SOLUTION: A least one conductive layer, two tunnel layers and at least two magnetic layers are laminated and at least one of the tunnel layers is pinched with the two magnetic layers and its resistance is changed due to the magnetized relative angle of the magnetic layers being changed. In such a tunnel magnetoresistive layer, at least one of the tunnel lavers one which will not be changed, regardless of the changes in magnetized relative angle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing head for a magnetic recording apparatus such as a magneto-optical disk, a hard disk, a digital data streamer (DDS) and a digital VTR used for an information communication terminal and the like. Angular velocity magnetic sensor for detecting speed, stress or acceleration sensor for detecting stress change, acceleration change, etc., or thermal sensor or chemical reaction sensor using change in magnetoresistance effect due to heat or chemical reaction
Also, the present invention relates to a magnetoresistive device widely used in magnetic memories typified by magnetic random access memories, magnetic switches, magnetic logic circuits, and the like.

[0002]

2. Description of the Related Art When a current is passed across an intermediate layer in a multilayer film having a ferromagnetic material / intermediate layer / ferromagnetic material as a basic structure, a giant magnetoresistance effect due to a GMR effect or a TMR effect may occur. Are known. When these elements are applied to a magnetic head, a memory, or the like, a change in resistance due to a change in the relative magnetization angle of the two magnetic members sandwiching the intermediate layer is detected as a change in element voltage with respect to a constant current. Therefore, in order to obtain a high output change, it is necessary to increase the element current at the same time as high MR. However, GMR
In the element, the element resistance is low, and due to the current density limit of the element,
It is difficult to obtain a high output voltage. In addition, the TMR effect has a problem of bias dependency that the higher the voltage applied to the element, the smaller the MR change. On the other hand, conventionally, in the GMR element, a device having a three-terminal configuration using hot electrons has been proposed (Japanese Patent Laid-Open No. 9-128719), and a ferromagnetic double tunnel junction has been proposed for the TMR element. (For example, Document 119 of the 119th meeting of the Japan Society of Applied Magnetics).

[0003]

However, the most preferred configuration of the ferromagnetic double tunnel junction has one free magnetic layer, two tunnel junctions and two fixed magnetic layers. The thickness of the free magnetic layer is generally about several nm or less, but the fixed magnetic layer requires at least 10 nm or more together with the antiferromagnetic material that fixes the magnetization. Become. Therefore, for example, when this element is used as a memory, the distance from the current line for generating the signal magnetic field to the free magnetic layer for recording the signal magnetic field increases, and the current consumption required for the magnetization reversal of the free magnetic layer increases. In addition, when this element is used for a shield type head, there is a problem that it is difficult to narrow the gap. On the other hand, in the most preferable configuration of the three-terminal element using the GMR element, the tunnel layer /
It has a configuration of non-magnetic layer 1 / magnetic layer 1 / non-magnetic layer 2 / magnetic layer 2 / semiconductor. In this device, since the hot electrons exceeding the tunnel layer need to pass through at least four or more nonmagnetic or magnetic layers constituting the base portion in a ballistic manner, the gain of the emitter current relative to the collector current is increased. Is extremely poor.

An object of the present invention is to provide a magnetic device having a relatively small layer thickness and a high output or a high current gain, which addresses the conventional problems.

[0005]

According to the present invention, at least one conductive layer, two tunnel layers and at least two magnetic layers are stacked, and at least one of the tunnel layers is formed. A tunnel magnetoresistive layer sandwiched between two magnetic layers and having a resistance changed by a change in the relative angle of magnetization of the two magnetic layers;
At least one of the magnetic devices is a tunnel layer that does not depend on a change in the relative magnetization angle. With the configuration of the present invention, bias dependency can be improved or high output can be obtained.

Further, in the above invention, the present invention comprises at least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2 in this order, and the magnetic layers 1 and 2 have different coercive forces. The change in the relative angle of magnetization between the magnetic layer 1 and the magnetic layer 2 is at least
This is a magnetic device that detects a change in resistance between the two. With the configuration of the present invention, bias dependency can be improved or high output can be obtained.

In the above invention, when the conductive layer 1 is a non-magnetic conductor, the element configuration is the simplest.

In the above invention, when the conductive layer 1 is a magnetic conductor and has substantially the same coercive force as the magnetic layer 1, the output is increased or the bias dependency is improved.

In the above invention, the magnetic layer 1 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 2 is a fixed magnetic layer whose magnetization rotation is more difficult than the magnetic layer 1, and the fixed magnetic layer has a high coercive force. High output can be obtained by magnetically coupling with a magnetic material, a laminated ferrimagnetic material, or an antiferromagnetic material.

In the above invention, if the resistance of the tunnel layer 1 is R1 and the resistance of the tunnel layer 2 is R2, 0.5
When xR2 ≦ R1 ≦ 100 × R2, the output is improved. When R1 is smaller than 0.5 × R2, the bias applied to the tunnel layer 2 increases, and the effect of improving the bias dependency decreases. If R1 is larger than 100 × R2, the output due to the change in magnetoresistance in the entire device decreases.

In the above invention, if the tunnel layer 1 and the tunnel layer 2 are formed of the same material, and the thickness of the tunnel layer 1 is D1 and the thickness of the tunnel layer 2 is D2, 0.9 × R
When the range is 2 ≦ R1 ≦ 1.5 × R2, the output is improved. If D1 is smaller than 0.9 × R2, the bias applied to the tunnel layer 2 increases, and the effect of improving the bias dependency decreases. When R1 is larger than 1.5 × R2, the output due to the change in magnetoresistance in the entire device decreases.

In the above invention, when the shortest distance between the tunnel layers 1 and 2 is L, 1 ≦ L ≦ 100 (n
When it is in the range of m), the effect of increasing the output or improving the bias dependency is large. If L is smaller than 1 nm, it is difficult for the magnetic layer 1 sandwiched between the tunnel layers to be a sufficiently continuous film. On the other hand, if L is larger than 100 nm, the distance of the electrons flowing between the tunnel layers becomes long, and spin scattering and the like are likely to occur, so that the bias dependency and the like are not sufficiently improved.

In the above invention, at least the magnetic layer 1, the tunnel layer 1, the magnetic layer 2, the tunnel layer 2, the magnetic layer 3, the tunnel layer 3, and the magnetic layer 4 are arranged in this order. When the magnetic layer 4 is a free magnetic layer (pinned magnetic layer), the magnetic layers 2 and 3 are fixed magnetic layers (free magnetic layer).
In a magnetic device which detects a change in the relative magnetization angle between the magnetic layer 4 and the magnetic layer 4 at least as a resistance change between the magnetic layer 1 and the magnetic layer 4, the bias dependency is further improved.

In the above invention, the present invention comprises at least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2 in this order, and the magnetic layers 1 and 2 have different coercive forces. The magnetic device has a conductive layer 1 as an emitter, a magnetic layer 1 as a base, and a magnetic layer 2 as a collector. With the configuration of the present invention, higher output can be obtained.

In the above invention, the present invention comprises at least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2, in which order, the magnetic layers 1 and 2 have different coercive forces. The magnetic device has a conductive layer 1 as a collector, a magnetic layer 1 as a base, and a magnetic layer 2 as an emitter. With the configuration of the present invention, higher output can be obtained.

In the above-mentioned invention, when the conductive layer 1 is a non-magnetic conductor, the element configuration becomes the simplest. When the conductive layer 1 is a magnetic conductor, a larger output change is obtained.

In the above invention, when the conductive layer 1 is a magnetic conductor and has substantially the same coercive force as the magnetic layer 1, a larger output change can be obtained.

In the above invention, the magnetic layer 1 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 2 is a fixed magnetic layer whose magnetization rotation is more difficult than the magnetic material 1, and the fixed magnetic layer has a high coercive force. A high output change can be obtained by magnetically coupling with a magnetic material, a laminated ferrimagnetic material, or an antiferromagnetic material.

In the above invention, if the resistance of the tunnel layer on the emitter side is represented by Re and the resistance of the tunnel layer on the collector side is represented by Rc, a high current gain can be obtained when Rc ≦ Re ≦ 10 ⁸ × Rc.

If Re is smaller than Rc, the bias applied to the tunnel layer 2 increases, and the current gain decreases. On the other hand, if Re is greater than 10 ⁸ × Rc, the current flowing through the element itself becomes small, making detection difficult.

In the above invention, when the shortest distance between the tunnel layers 1 and 2 is L, a high output or a high current gain can be obtained when 1 ≦ L ≦ 100 (nm). If L is smaller than 1 nm, it is difficult for the magnetic layer 1 sandwiched between the tunnel layers to be a sufficiently continuous film. On the other hand, if L is larger than 100 nm, the distance of electrons flowing between the tunnel layers becomes longer,
Output or current gain decreases.

Also, the present invention comprises at least a magnetic layer 1, a tunnel layer 1, a magnetic layer 2, and a semiconductor 1. In this case, the magnetic layer 1 and the magnetic layer 2 have different coercive forces. This is a magnetic device having a magnetic layer 2 as a base and a semiconductor as a collector. With the configuration of the present invention,
High output can be obtained.

In the above-mentioned invention, a good Schottky interface can be formed at the interface with the magnetic layer 2 by interposing the conductive layer 1 at least between the magnetic layer 2 and the semiconductor.

In the above invention, the magnetic layer 2 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 1 is a fixed magnetic layer whose magnetization rotation is more difficult than the magnetic material 1, and the fixed magnetic layer has a high coercive force. High output can be obtained by magnetically coupling with a magnetic material, a laminated ferrimagnetic material, or an antiferromagnetic material.

In the above invention, since the tunnel layer is an oxide, nitride or oxynitride of Al, a stable tunnel layer can be obtained.

In the above invention, a high output or a high current gain can be obtained by setting the bias applied to at least one tunnel layer to 300 mV or more and 3 V or less.

By using the magnetoresistive device of the invention, it is possible to manufacture a magnetic memory that can obtain a high output at the time of reading.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic device according to the present invention will be described with reference to the drawings. First, FIG.
This is a structural example of a magnetic device using a non-magnetic layer and configured in the order of a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2. The magnetic layer 1 and the magnetic layer 2 have different coercive forces, and detect a change in relative magnetization angle between the magnetic layer 1 and the magnetic layer 2 as at least a resistance change between the conductive layer 1 and the magnetic layer 2. With such a configuration, the bias dependency of the MR change is improved as compared with a TMR element having a simple configuration of a magnetic layer / tunnel layer / magnetic layer. Conductive layer 1
The bias generated when a current flows between the tunnel layer 1 and the magnetic layer 2 is mainly shared according to the resistance ratio between the tunnel layers 1 and 2. However, the bias dependence of the magnetic layer 1 / tunnel layer 2 / magnetic layer 2 of the present configuration, which is inferred from the shared bias, is improved as compared with a simple TMR element. As a result, the output of the entire device with respect to the change in external magnetic energy is larger than that of a simple TMR device.

Although this phenomenon is not clear,
With at least two tunnel layers interposed, the energy distribution of the electrons that are conducted through each magnetic layer changes,
It is considered that the influence of the band structure of the magnetic layer changed, or that cotunneling or the like was involved.

In the above configuration, a nonmagnetic conductive layer may be interposed at the interface between the tunnel layer 1 and the magnetic layer 1. This non-magnetic conductive layer has a function of, for example, relaxing interface stress between the magnetic layer 1 and the tunnel layer 1.

Here, materials used for the magnetic layer 1 or the magnetic layer 2 include Fe, Co, Ni, FeCo alloy, NiFe alloy,
CoNi alloy, NiFeCo alloy, or FeN, FeTiN, FeAlN,
FeSiN, FeTaN, FeCoN, FeCoTiN, FeCo (Al, Si) N, FeCoT
TMA represented by nitride, oxide, carbide, boride, fluoride magnetic material such as aN (T is at least one selected from Fe, Co, Ni, M is Mg, Ca, Ti, Zr , Hf, V, Nb, Ta, Cr,
At least one selected from Al, Si, Mg, Ge, Ga, and A is at least one selected from N, B, O, F, C) or (Co, Fe) M (M is Ti , Zr, Hf, V, Nb, Ta, Cu ,,
B) or FeCr, FeSi
Al, FeSi, FeAl, FeCoSi, FeCoAl, FeCoSiAl, FeCoTi, F
e (Ni) (Co) Pt, Fe (Ni) (Co) Pd, Fe (Ni) (Co) Rh, Fe (Ni) (C
o) TL represented by Ir, Fe (Ni) (Co) Ru, FePt, etc. (T is Fe, C
at least one selected from o and Ni, L is Cu, Ag, Au, Pd,
Pt, Rh, Ir, Ru, Os, Ru, Si, Ge, Al, Ga, Cr, Mo, W,
V, Nb, Ta, Ti, Zr, Hf, La, Ce, Pr, Nd, Pm, Sm, E
at least one selected from u, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu), or Fe ₃ O ₄ or XMnSb, (X is Ni, Cu, Pt At least one selected from the group consisting of), a half-metal material represented by LaSrMnO, LaCaSrMnO, CrO ₂ , or QDA (Q is Sc, Y, a lanthanoid,
At least one selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Ni, Zn, A is at least one selected from C, N, O, F, S, D is V, Cr , Mn, Fe, Co, Ni) or GaMnN, AlMnN, GaAlMnN, AlBMnN
(R is one kind selected from B, Al, Ga, Ga, In, D is D
Is one selected from V, Cr, Mn, Fe, Co, Ni, and A is C, N,
Magnetic semiconductors represented by O, P, and S), spinel oxides such as perovskite oxides and ferrites, and garnet oxides are preferred.

The material used for the tunnel layer 1 or the tunnel layer 2 may be any material as long as it is an insulator or a semiconductor. Particularly, Mg, Ti, Zr, Hf, V, Nb, Ta, Cr
Including IIa to VIa, lanthanoids including La and Ce, Zn,
Elements selected from IIb to VIb including B, Al, Ga, Si,
The compound is preferably a compound with at least an element selected from F, O, C, N, and B.

FIG. 1 shows that the conductive layer 1 is a non-magnetic conductive layer.
In the configuration (1), since the conductive layer 1 also functions as an electrode for introducing a current into the element, the element configuration is simplified. Preferred materials for the conductive layer 1 include Cu, Al, Ag, Au, Pt, and TiN, as long as the material has a resistivity of 100 μΩcm or less. These non-magnetic conductive materials include the tunnel layer 1 and the magnetic layer 1.
Between them may be inserted as a nonmagnetic conductive layer.

FIG. 2 shows a magnetic device in which the conductive layer 1 is a magnetic conductor and has substantially the same coercive force as the magnetic layer 1. The conductive layer 1 and the magnetic layer 1 respond to external magnetic energy.
The magnetization is rotated in substantially the same manner. With such a configuration, an increase in output of the element or an improvement in bias dependency can be seen. This phenomenon may be caused by an effect such as an improvement in apparent polarizability due to filtering of up spin or down spin between the magnetic layers sandwiching the tunnel layer 1. Unknown. In the above configuration, a nonmagnetic conductive layer may be interposed at the interface between the tunnel layer 1 and the magnetic layer 1. This nonmagnetic conductive layer facilitates the rotation of the magnetization of the magnetic layer 1 by, for example, relaxing the interface stress between the magnetic layer 1 and the tunnel layer 1.

In the magnetic device shown in FIG. 1 or 2, one of the magnetic layer 1 and the magnetic layer 2 is a free magnetic layer, and the other is a fixed magnetic layer. 1 and the relative angle of magnetization of the magnetic layer 2 are clarified, and as a result, a high output can be obtained.

In particular, the magnetic layer 1 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 2 is a fixed magnetic layer whose magnetization rotation is more difficult than the magnetic material 1, and the fixed magnetic layer is a high coercivity magnetic material. ,
High output can be obtained by magnetically coupling with the laminated ferrimagnetic material or antiferromagnetic material.

The magnetic layer 2, which is a fixed magnetic layer, is made of a high coercive force magnetic material, a laminated ferrimagnetic material, an antiferromagnetic material, or a laminated ferrimagnetic material and an antiferromagnetic material placed on the surface opposite to the tunnel layer 2. It is desirable to make magnetization rotation difficult by magnetically coupling with the multilayer film.

If the magnetic layer 1 is a fixed magnetic layer and the magnetic layer 2 is a free magnetic layer by magnetic coupling with another material, the bias characteristics may not be sufficiently improved. This is presumably because the thickness of the high coercive force magnetic material, the laminated ferrimagnetic material, or the antiferromagnetic material increases the distance between the tunnel layer 1 and the tunnel layer 2 or facilitates spin inversion. However, when the pinned magnetic layer is shape anisotropic or the pinned magnetic layer itself is a material having a high coercive force, the magnetic layer 1 may be a pinned magnetic layer.

As the high coercive force magnetic material having the above structure, CoP
Materials having a holding force of 100 Oe or more, such as t, FePt, CoCrPt, CoTaPt, FeTaPt, and FeCrPt, are preferable.

As the antiferromagnetic material, PtMn, PtPdMn,
FeMn, IrMn, NiMn and the like are preferable.

The laminated ferrimagnetic material has a multilayer structure of a magnetic material and a non-magnetic material, and the magnetic material used here is FeCo, CoFeNi, CoNi, CoZrT containing Co or Co.
a, CoZrB It is preferable to use a CoZrNb alloy or the like, and as the nonmagnetic material, it is preferable to use Cu, Ag, Au, Ru, Rh, Ir, Re, Os, or an alloy or oxide of these metals.

If the resistance of the tunnel layer 1 is R1 and the resistance of the tunnel layer 2 is R2, the relationship between R1 and R2 is
When 0.5 × R2 ≦ R1 ≦ 100 × R2,
Output improves. When R1 is smaller than 0.5 × R2, the bias applied to the tunnel layer 2 increases, and the effect of improving the bias dependency decreases. R1 is 100 × R
If it is larger than 2, the output due to a change in magnetoresistance in the entire device will decrease. Since the value of the tunnel resistance changes non-linearly due to the bias, R1 and R2 here are values at a low bias of about 20 mV. The R value of each layer can be changed by controlling the thickness of the tunnel layer or the barrier height. Therefore, it can be manufactured by selecting the thickness or type of the tunnel material described above.

In the above structure, the tunnel layer 1
If the thickness of the tunnel layer 1 is D1 and the thickness of the tunnel layer 2 is D2, 0.
When 9 × R2 ≦ R1 ≦ 1.5 × R2, the output is improved. If D1 is smaller than 0.9 × R2, the bias applied to the tunnel layer 2 increases, and the effect of improving the bias dependency decreases. When R1 is larger than 1.5 × R2, the output due to the change in magnetoresistance in the entire device decreases. Here, the same material refers to Al, Mg, Hf,
Oxides, nitrides, and oxynitrides including Ta, Si, and B are particularly preferable.

In the above structure, when the shortest distance between the tunnel layers 1 and 2 is L, 1 ≦ L ≦ 100 (n
When it is in the range of m), the effect of increasing the output or improving the bias dependency is large. If L is smaller than 1 nm, it is difficult for the magnetic layer 1 sandwiched between the tunnel layers to be a sufficiently continuous film. On the other hand, if L is larger than 1, the distance of electrons flowing between the tunnel layers becomes long, and spin scattering and the like are likely to occur, so that the bias dependency and the like are not sufficiently improved.

In the above configuration, a magnetic device using two tunnel layers has been described. However, a combination of the configurations 1 or 2 described above, for example, three or more layers shown in FIGS. In the configuration using the tunnel layer, high bias dependency or high output can be realized by the same effect as described above.

For example, in the above invention, at least
The magnetic layer 1, the tunnel layer 1, the magnetic layer 2, the tunnel layer 2, the magnetic layer 3, the tunnel layer 3, and the magnetic layer 4 are arranged in this order, and the magnetic layers 1 and 4 are free magnetic layers (pinned magnetic layers). At this time, the magnetic layer 2 and the magnetic layer 3 are fixed magnetic layers (free magnetic layers), and between the magnetic layer 1 and the magnetic layer 2 and between the magnetic layer 3 and the magnetic layer 3.
In a magnetic device which detects a change in the relative magnetization angle between the magnetic layer 4 and the magnetic layer 4 at least as a resistance change between the magnetic layer 1 and the magnetic layer 4, the bias dependency is further improved. FIG.
Shows an embodiment of this device. FIG. 7 shows a configuration in which the free magnetic layer is shared in the configuration of FIG. 2 and connected in series, and the basic principle is the same as that of FIG. In this configuration, the bias dependency is further improved by connecting the tunnel layers in series to reduce the bias applied to the tunnel layer 1 or the tunnel layer 3 and the like. Where, in particular,
For the same reason as described above, the resistance R2 of the tunnel layer 2 is different from the resistances R1 and R3 of the remaining tunnel layers by 0.5 × R
It is desirable that the relationship of 1 (R3) ≦ R2 ≦ 100 × R1 (R3) is satisfied. In this configuration, the free magnetic layer and the pinned magnetic layer are exchanged, and at least the configuration of the free magnetic layer 1, the tunnel layer 1, the fixed magnetic layer 1, the tunnel layer 2, the fixed magnetic layer 3, and the free magnetic layer 2 is adopted. , The resistances R1 and R3 of the tunnel layers 1 and 3 are equal to the resistance R2 of the tunnel layer 2
And 0.5 × R2 ≦ R1, R3 ≦ 100 × R2. In the above configuration, the tunnel layer 2
A non-magnetic conductive layer may be interposed at the interface between the magnetic layer 1 and the tunnel layer 2 or the magnetic layer 2. This nonmagnetic conductive layer
The interface stress between the tunnel layer 2 and the magnetic layer 1 or the magnetic layer 2 is reduced.

The configuration of the present invention represented by FIG. 1 and FIG. 2 can be realized, for example, as shown in FIG. 3 by using a normal thin film process and a fine processing process. Each magnetic layer,
Pulse laser deposition (PLD), ion beam deposition (IBD), cluster ion beam or RF, D
It can be produced by a sputtering method such as C, ECR, helicon, ICP or a facing target, a PVD method such as MBE, ion plating method, or the like, a CVD method, a plating method, or a sol-gel method.

In particular, when the tunnel layer is an insulator,
Including Mg, Ti, Zr, Hf, V, Nb, Ta, Cr
Lanthanoids including Ia, La, Ce, Zn, B, Al, Ga, Si
Elements selected from IIb to VIb containing, or alloys or
A thin film precursor of the compound is prepared, and this is any of F, O, C, N,
Suitable for containing elements, molecules or ions, radicals, etc.
Almost completely by reacting in a suitable atmosphere, temperature and time
It can be manufactured by fluoridation, oxidation, carbonization, nitridation, and boration. Ma
In addition, as a thin film precursor, F, O, C, N, and B are contained below the stoichiometric ratio.
First, a nonstoichiometric compound was prepared, and this was selected from F, O, C, N, and B.
Suitable for containing elements, molecules or ions, radicals, etc.
Atmosphere, temperature, time, and reactivity. these
For example, using the sputtering method, tunnel insulation
Al as layer_TwoO _ThreeWhen producing Al or AlO_X(X ≦ 1.
5) in Ar atmosphere or Ar + O_TwoFilm formation in atmosphere
O these_TwoOr O_Two+ React in inert gas
Can be realized by repeating. In addition, plasma and radio
ECR discharge, glow discharge, RF discharge, helicopter
It can be generated by ordinary means such as a capacitor or ICP.

The fine processing includes physical or chemical etching methods such as ion milling, RIE and FIB used in a semiconductor process and a GMR head manufacturing process, and a stepper or EB for forming a fine pattern.
This can be achieved by combining photolithography techniques using a method or the like. Also, for the purpose of flattening the surface of electrodes, etc.,
It is also effective to use CMP or cluster ion beam etching.

Next, FIGS. 8 and 9 show at least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2 in this order, and the magnetic layers 1 and 2 have different coercive forces. The conductive layer 1 is an emitter and the magnetic layer 1 is a base.
2 shows a structural example of a magnetic device using the magnetic layer 2 as a collector. Each shows a structure in which a positive bias can be applied to the base with respect to the emitter and to the collector with respect to the base. Tunnel electrons flow from the emitter through the tunnel layer 1 due to the tunnel effect. Some of the electrons that have flowed are affected by the band structure of the magnetic layer 1 and spin polarization is performed. Among the polarized conduction electrons, those having high energy tend to pass through the tunnel layer 2. At this time, the magnitude of the tunnel current (collector current) changes according to the magnitude of the relative magnetization angle between the magnetic layers 1 and 2. Alternatively, the one that satisfies the cotunneling condition from the emitter to the magnetic layers 1 and 2 reaches the magnetic layer 2. In this magnetic device, furthermore, changing the emitter voltage, or in addition to the emitter voltage,
By changing the collector voltage, the collector current can be controlled. By optimizing these bias voltages, a change in the relative magnetization angle due to external magnetic energy can be obtained as a larger output.

Incidentally, a nonmagnetic conductive layer may be interposed at the interface between the tunnel layer 1 and the magnetic layer 1. This nonmagnetic conductive layer functions as an electrode for relaxing the interface stress between the magnetic layer 1 and the tunnel layer 1 or for providing a base potential.

Next, FIGS. 10 and 11 show at least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2 in this order, and the magnetic layers 1 and 2 have different coercive forces. An example of the structure of a magnetic device having a conductive layer 1 as a collector, a magnetic layer 1 as a base, and a magnetic layer 2 as an emitter is shown. The electrons flowing from the emitter mainly flow into the base as tunnel electrons reflecting the polarizability between the magnetic layer 2 and the magnetic layer 1 and the relative magnetization angle. Among the injected electrons, those with high energy try to conduct further to the tunnel layer 1 side, but are scattered by the band structure during conduction in the magnetic layer 1. As a result, of the remaining electrons, electrons having energy exceeding the tunnel layer 1 become the collector current. Alternatively, an electron that satisfies the cotunneling condition from the emitter to the base and the collector becomes the collector current. This magnetic device is further modified by changing the emitter voltage, or by changing the collector-voltage in addition to the emitter voltage.
The collector current can be controlled. By optimizing these bias voltages, external magnetic energy
, The change in the relative magnetization angle can be obtained as a larger output.

Incidentally, a non-magnetic conductive layer may be interposed at the interface between the tunnel layer 1 and the magnetic layer 1. This nonmagnetic conductive layer alleviates the interface stress between the magnetic layer 1 and the tunnel layer 1 or functions as an electrode for a base potential.

In the above configuration, FIG.
When the conductive layer 1 is a non-magnetic conductor, as in the case of 0, the conductive layer 1 can be made of a common material with the electrodes, thereby simplifying element fabrication.

In the above configuration, FIG. 9 or FIG.
When the conductive layer 1 is a magnetic conductor and has substantially the same coercive force as the magnetic layer 1 as in 1, the change in the collector current due to the change in the relative magnetization angle becomes large. This is the case in FIG.
It is considered that an effect such as an improvement in apparent polarizability is caused by an up spin or a down spin of the magnetic material sandwiching the tunnel layer being filtered by the two magnetic layers. In addition, in the case of FIG. 11, it is necessary to cause a spin tunnel between the magnetic layer 1 and the (magnetic) conductive layer 1, which further limits the conditions under which a collector current flows with respect to external magnetic energy. .

In the magnetic device having the above structure, one of the magnetic layer 1 and the magnetic layer 2 is a free magnetic layer, and the other is a fixed magnetic layer.
The relative magnetization angles of the magnetic layers 1 and 2 are clarified, and the output change due to external magnetic energy is increased. In particular, for example, in the magnetic device of FIGS.
By using the magnetic layer 1 as a free magnetic layer and the magnetic layer 2 as a fixed magnetic layer, the relative angle of magnetization of the magnetic layers 1 and 2 with respect to external magnetic energy is clarified, and the external magnetic energy is increased. The output change due to-is increased.

Here, the magnetic layer 2 serving as the pinned magnetic layer has a high coercive force magnetic material placed on the surface opposite to the tunnel layer 2.
It is desirable to make the magnetization rotation difficult by magnetically coupling the multilayer ferrimagnetic material, the antiferromagnetic material, or the multilayer film of the multilayer ferrimagnetic material and the antiferromagnetic material. With the above configuration,
When the magnetic layer 1 is a fixed magnetic layer, output characteristics may not be sufficiently improved. This is presumably because the thickness of the high coercive force magnetic material, the laminated ferrimagnetic material, or the antiferromagnetic material increases the distance between the tunnel layer 1 and the tunnel layer 2 or facilitates spin inversion. However, when the pinned magnetic layer is shape anisotropic or the pinned magnetic layer itself is a material having a high coercive force, the magnetic layer 1 may be a pinned magnetic layer.

In the above structure, when the resistance of the tunnel layer on the emitter side is represented by Re and the resistance of the tunnel layer on the collector side is represented by Rc, a high current gain is obtained when Rc ≦ Re ≦ 10 ⁸ × Rc. . The energy of electrons entering the base from the emitter side by the tunnel effect is considered to be only those near the Fermi level of the emitter. The electrons entering the base lose energy due to collision with the lattice or the like, but part of the electrons reach the collector-side tunnel layer. Here, the electrons exceeding the tunnel layer flow into the collector. Therefore, when the energy of electrons that are going to flow from the emitter side to the base exceeds the tunnel barrier on the collector side, the collector-current ratio (current gain) to the emitter current can be increased. The condition for the collector current to flow is the emitter-base
Is determined by the height of the collector-side tunnel barrier with respect to the base Fermi level with respect to the difference in Fermi level between qV _EB and qV _EB . At the same time, it is desirable that the barrier height of the emitter is higher than the barrier height of the collector.

If these are expressed from an experimental point of view as resistance values that can be easily measured as a device, Re is represented by Rc
When the value is larger than Re, the current gain increases because the number of electrons reaching the collector increases. On the other hand, when Re is greater than 10 ⁸ × Rc, noise or the like is likely to occur.

This is because the tunnel resistance becomes smaller as the thickness becomes smaller when the barrier height is the same, and becomes smaller as the barrier height becomes smaller when the thickness is the same. In addition, in the case of a tunnel layer made of the same material, the thinner the thickness is, the lower the barrier height tends to be. In addition, from the viewpoint of fabrication, when the same emitter current flows, if the tunnel resistance Re on the emitter side is high, there is an advantage that qV _EB can be easily increased and the amount of current can be suppressed. Note that the tunnel resistance generally varies non-linearly with a bias, so that Rc and Rc
e is a value at a relatively low bias of about 20 mV or less.

In the above structure, if the shortest distance between the tunnel layers 1 and 2 is L, 1 ≦ L ≦ 100 (n
In the range of m), a high current gain and a high current gain or a change in output with respect to external magnetic energy are obtained.
If L is smaller than 1 nm, it is difficult for the magnetic layer 1 sandwiched between the tunnel layers to be a sufficiently continuous film. If L is larger than 100 nm, it is difficult for electrons from the emitter to reach the collector.

Next, FIGS. 12 and 13 show that at least the magnetic layer 1, the tunnel layer 1, the magnetic layer 2, and the semiconductor 1 are arranged in this order, and the magnetic layer 1 and the magnetic layer 2 have different coercive forces. 1 shows an example of the structure of a magnetic device having an emitter 1, a magnetic layer 2 as a base, and a semiconductor 1 as a collector. The electrons flowing from the emitter mainly flow into the base as tunnel electrons reflecting the polarizability and the relative magnetization angle between the magnetic layers 1 and 2. Among the injected electrons, those having relatively high energy try to conduct to the semiconductor 1, but are scattered by the band structure of the magnetic layer 2 during the conduction. Among them, the electrons having energy exceeding the Schottky barrier at the interface between the semiconductor 1 and the magnetic body 2 become the collector current. This magnetic device can further change the emitter voltage, or in addition to the emitter voltage,
By changing the collector voltage, the collector current can be controlled. By optimizing these bias voltages, a change in the relative magnetization angle due to external magnetic energy can be obtained as a larger output.

In the structure shown in FIGS. 12 and 13, since the conductive layer 1 is interposed at least between the magnetic layer 2 and the semiconductor 1, a good Schottky interface can be formed at the interface with the magnetic layer 2. This preferred conductive layer 1 is, for example,
When the conductive metal is good and the semiconductor 1 is a Si-based semiconductor, a silicide such as NiSi ₂ or CoSi ₂ is good.

In the magnetic device having the above-described structure, one of the magnetic layers 1 and 2 is a free magnetic layer in which magnetization rotation is easy, and
The other is a fixed magnetic layer in which magnetization rotation is difficult, and the fixed magnetic layer is magnetically coupled to a high coercive force magnetic material, a laminated ferrimagnetic material or an antiferromagnetic material, so that magnetic energy from the outside is reduced. The relative magnetization angles of the magnetic layer 1 and the magnetic layer 2 can be made clear, and the output change can be increased.

In particular, in the magnetic device of FIGS. 12 and 13, for example, the magnetic layer 2 is a free magnetic layer whose magnetization rotation is easy, and the magnetic layer 1 is a fixed magnetic layer whose magnetization rotation is more difficult than the magnetic layer 2. The fixed magnetic layer is magnetically coupled to a high coercive force magnetic material, a laminated ferrimagnetic material, or an antiferromagnetic material, so that the relative magnetization of the magnetic layers 1 and 2 with respect to external magnetic energy is reduced. The angle can be made clear and the output change can be increased. Here, the magnetic layer 1, which is the pinned magnetic layer, is made of a high coercive force magnetic material, a laminated ferrimagnetic material, an antiferromagnetic material, or a laminated ferrimagnetic material placed on the surface opposite to the tunnel layer 1. It is desirable to make the magnetization rotation difficult by magnetically coupling with the multilayer film of the body. In the above configuration, when the magnetic layer 2 is a fixed magnetic layer, the output characteristics may not be sufficiently improved. This is presumably because the distance between the tunnel layer 1 and the semiconductor 1 is increased or the spin inversion is likely to occur due to the thickness of the high coercive force magnetic material, the laminated ferrimagnetic material, or the antiferromagnetic material. However, when the pinned magnetic layer has a shape anisotropy or the pinned magnetic layer itself is a material having a high coercive force, the magnetic layer 2 may be a pinned magnetic layer.

In the above-described structure, a stable tunnel layer can be obtained particularly when the tunnel layer is made of an oxide, nitride or oxynitride of Al.

Further, in the above-described structure, a high output or a high current gain can be obtained by being characterized in that a bias applied to at least one tunnel layer is not less than 300 mV and not more than 3 V. Below 300 mV, these output values are small, and above 3 V, the effect of inelastic scattering of electrons cannot be ignored.

Further, as described above, the free magnetic layer has a structure in which at least one non-magnetic material and two magnetic materials are laminated, and the magnetic material sandwiching the non-magnetic material has a magnetostatic coupling or an anti-magnetic force. Magnetic coupling may be performed. Here, in the case of magnetostatic coupling, any conductive non-magnetic material may be used.
A thickness of at least nm is required. In the case of antiferromagnetic coupling, a conductive nonmagnetic material, preferably Cu, Ag, Au,
Ru, Rh, Ir, Re, Os or alloys or oxides of these metals, preferably with a thickness of 0.2 to 1.1 nm.
When antiferromagnetic coupling is performed, the free magnetic layer needs to have a small amount of magnetic moment leaking from the antiferromagnetic coupling. The free magnetic layer, which is a multilayer film of these magnetic and non-magnetic materials, facilitates the rotation of the magnetization of the free magnetic layer when the magnetic device having the above configuration is miniaturized.

Further, by using the magnetoresistive device having the above-described structure, a magnetic memory which can obtain a high output at the time of reading can be manufactured.

Next, FIG. 14 shows an example of a random access memory using the magnetic device having the above configuration as a memory element. The element used as the memory may have any configuration of the magnetic device having the above configuration. The elements are arranged in a matrix at the intersections of bit lines and word lines made of Cu or Al as shown in, for example, A1 of FIG. 14, and a signal current is applied to each line. Signal information is recorded by a two-current coincidence method using a synthetic magnetic field generated at the time.

A basic example of the write operation and the read operation by the current of the magnetic memory device in FIGS. 15 to 17 will be described. In each of the drawings, the magnetic device shown in FIG. 1 is used as a memory element as an example.

FIG. 15 shows a configuration in which a switching element typified by an FET is provided for each element in order to individually read the magnetization state of the element. This random access memory can be easily configured on a CMOS substrate. In FIG. 16,
A configuration using a non-linear element or a rectifying element for each element is shown. Here, as the nonlinear element, a varistor, a tunnel element, or a three-terminal element having the above configuration may be used. This random access memory can be manufactured on a glass substrate at low cost only by increasing the process of forming a diode. 17 and FIG. 1 and FIG.
In this configuration, elements such as switching elements for element isolation or rectifying elements such as 6 are not used, and elements are directly arranged at intersections of word lines and bit lines. Therefore, in FIG. 17, since current flows across a plurality of elements at the time of reading, it is preferable that the number of elements is 10,000 or less from the viewpoint of reading accuracy. With 10,000 elements or more, sufficient output cannot be obtained.

FIGS. 15 to 17 each show a case where the bit line is used together with a sense line for reading a change in resistance by flowing a current through the element. And a bit line may be separately provided. At this time, it is preferable that the bit line is arranged at a position electrically insulated from the element and parallel to the sense line. In the case of current writing, the distance between a word line, a bit line and a memory cell is 500 n from the point of power consumption.
m or less.

When the above magnetic device is used as a memory, the free magnetic layer is formed in a square shape as shown in FIG. 18A and provided with shape anisotropy, and more preferable shapes are shown in FIGS. It is a non-square type as shown in 5). With these shapes, the rectangular shape of the memory is improved, and the reliability of memory retention is also improved.

(Example 1) The following samples were produced on a Si / SiO ₂ substrate by using multi-source sputtering.

Sample 1 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe (3) / Ru (0.9) / CoFe
(3) / AlO (1.0) / Fe (2) / Ta (25) Sample 2 Ta (3) / Cu (50) / Ta (3) / CoFe (3) / AlO (1.0) / Fe (2) / AlO (1.3)
/ Ta (25) Sample 3 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe (3) / Ru (0.9) / CoFe
(3) / AlO (1.0) / Fe (2) / AlO (1.3) / Ta (25) (Unit: nm) Here, the value in () of AlO () is the design thickness of Al before oxidation treatment. In practice, Al was formed into a film having a thickness of 0.3 to 0.7 nm and then oxidized in an oxygen-containing atmosphere.
Each film is finely processed into a mesa shape as shown in Fig. 3 and Cu (50) / Ta (3) is formed as an upper electrode, and then heat-treated at 280 ° C in a 5 KOe magnetic field to give unidirectional anisotropy to PtMn. Granted.

Here, the element cross-sectional area of each sample is 1.5 μm × 3 μm. The sample 1 has a configuration of a normal spin valve type TMR, and the samples 2 and 3 have a configuration according to FIG.

The lower electrode Ta (3) / Cu (50) and the upper electrode
The bias dependence of MR was measured by determining the change in magnetoresistance (MR) when the current flowing between Cu (50) / Ta (3) was varied.

FIG. 19 shows the result of Sample 1 and FIG. 20 shows the result of Sample 3. The figure shows the bias dependency of the MR change and the bias dependency of the output.
While the maximum value of the output of Sample 1, which is a normal spin-valve TMR element, is about several tens of mV, Sample 3 made of the same magnetic material clearly shows an increase in output. Further, it can be seen that the bias dependence of the MR in Sample 3 is different from the result obtained by simply adding a tunnel resistance of AlO (1.3) to Sample 1 in series. Sample 1 had an element resistance of 400 Ωμm ^{2 and} Sample 3 had an element resistance of about ² kΩμm ² . From these facts, Sample 3 has a higher resistance AlO (1.3) tunnel layer than Sample 1, so that electrons flowing in the element include those having higher energy than the Fermi level. This may reflect the band structure at a higher energy in the magnetic layer, or may be a result of a phenomenon such as co-tunneling due to the two tunnel layers.

On the other hand, sample 2 obtained higher bias dependency and output than sample 1, but had lower values than sample 3. This is because sample 3 is an antiferromagnetic substance PtMn
This is probably because the pinned magnetic layer was formed by making the CoFe (3) / Ru (0.9) / CoFe (3) laminated film having a laminated ferri structure into multiple layers.

Next, the following multilayer film was prepared by replacing Fe of Sample 2 with FeCo.

Sample 4 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe / Ru (0.9) / CoFe (3) / A
lO (1.0) / FeCo (2) / Ta (25) Sample 5 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe / Ru (0.9) / CoFe (3) / A
lO (1.0) / FeCo (2) / AlO (1.3) / Ta (25) FIG. 21 shows the measurement results of the bias dependence of Sample 5. Sample 5 exhibited output asymmetry, especially on the high bias side. Further, the output on the positive bias side of this sample obtained a value larger than the maximum value of sample 4.

In addition to the above, as a result of implementing the above-described materials in the embodiment, at least the conductive layer 1
The tunnel layer 1, the magnetic layer 1, the tunnel layer 2, and the magnetic layer 2 are arranged in this order. The magnetic layer 1 and the magnetic layer 2 have different coercive forces, and the change in the relative magnetization angle between the magnetic layer 1 and the magnetic layer 2 Is a magnetic device that detects at least a change in resistance between the conductive layer 1 and the magnetic layer 2, it is possible to improve the bias dependency or obtain a higher output than the conventional TMR element. Was. The bias conditions for obtaining the maximum output with this configuration depend on the material used for the magnetic layer, but the bias applied to either the tunnel layer 1 or the tunnel layer 2 was in the range of 300 mV to 3 V.

Further, the magnetic layer 1 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 2 is a fixed magnetic layer whose magnetization rotation is more difficult than that of the magnetic layer 1, and the fixed magnetic layer is a laminated ferrimagnetic material or an antiferromagnetic material. Higher output was obtained by magnetic coupling with ferromagnetic material.

Although AlO is used as the tunnel layer in the above description, a configuration using AlN or AlON instead of AlO may be used.
Improvement of bias dependency and high output were achieved. Here, AlN and AlON were produced by forming Al and then nitriding in nitrogen plasma or oxynitriding in oxynitrogen plasma.

Example 2 The following samples were prepared on a Si / SiO ₂ substrate by using multi-source sputtering.

Sample 1 Ta (3) / Cu (50) / Ta (3) / NiFeCr (4) / PtMn (20) / CoFe (3) / Ru
(0.9) / CoFe (3) / AlO (1.0) / NiFe (2) / AOl (1.6) / Ta (25) Sample 2 Ta (3) / Cu (50) / Ta (3) / NiFeCr (4) / PtMn (20) / CoFe (3) / Ru
(0.9) / CoFe (3) / AlO (1.0) / NiFe (2) / AOl (1.6) / NiFe (2) / Ta
(25) (Unit: nm) Here, the value in () of AlO () is the design film thickness of Al before the oxidation treatment. NiFeCr is a base layer for improving the orientation of PtMn. The fabricated film is finely processed into a mesa shape as shown in FIG.
After Cu (50) / Ta (3) was formed as the upper electrode, it was heat-treated at 280 ° C. in a 5 KOe magnetic field, and the bias dependence of each magnetoresistance (MR) change was measured. Here, the sample 1 has a configuration according to FIG. 1A, and the sample 2 has a configuration according to FIG. The element cross-sectional area of each sample is 1.5 μm
× 3 μm.

Table 1 shows a comparison between the output of Sample 1 and the output of Sample 2.

[0089]

[Table 1]

As described above, the conductive layer 1 is a magnetic conductor,
When the magnetic layer 1 has substantially the same coercive force, a high output is obtained.
Alternatively, the bias dependency was improved.

Example 3 The following samples were measured on a Si / SiO ₂ substrate by using multi-source sputtering.

Sample 1 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe (3) / Ru (0.9) / CoFe
(3) / AlO (1.0) / NiFeCo (2) / Ta (25) Samples 2-6 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe (3) / Ru (0.9 ) / CoFe
(3) / AlO (1.0) / NiFeCo (2) / AlO (d) / Ta (25) (unit: nm) Here, D2 of AlO (D2) is 0.8 to 1.
It is changed up to 6. 280 ° C for each sample
After heat treatment in 5KOe magnetic field, mesa processing was performed to form Cu (50) / Ta (3) as the upper electrode, and the bias dependence of the magnetoresistance (MR) change was measured. Note that the element cross-sectional area of each sample is 1.5 μm × 3 μm.

Table 2 shows the result of comparison between the maximum output P1 that can be taken by the sample 1 and the maximum output P2 that can be taken by the samples 2 to 6. R2 / R1 in the table refers to Sample 2
6 has a minimum resistance of AlO (D
2) tunnel resistance R2 and AlO (1.0) tunnel resistance R
This is a value obtained by assuming that it is a simple sum of R1 (R1 + R2), and assuming that the element resistance taken by the sample 1 with a low bias is also substantially the tunnel resistance R1 of AlO (1.0). In the table, D2 / D1 is a comparison between the thickness of Al of Samples 2 to 6 and the thickness of Al of Sample 1.

[0094]

[Table 2]

From the above results, assuming that the resistance of the tunnel layer 1 is R1 and the resistance of the tunnel layer 2 is R2 according to the above definition, when the resistance is in the range of 0.5 × R2 ≦ R1 ≦ 100 × R2, the output is Is improved.

The resistance values of the above-mentioned experiments and samples 2 to 6 show the case where the resistance values of the two tunnel layers can be regarded as a simple sum.

Actually, when an effect of changing an apparent resistance value is included, such as co-tunneling or Cron blockade, for example, as in the present embodiment, when a tunnel layer made of the same material is used, a tunnel layer is used. Assuming that the thickness of D1 is D1 and the thickness of the tunnel layer 2 is D2, the output is improved when 0.9 × D2 ≦ D1 ≦ 1.5 × D2 in consideration of variations in fabrication.

The range based on the film thickness ratio is based on the film thickness of Al which is a precursor for forming the tunnel layer. However, the same ratio may be considered when insulators having the same composition are formed as the tunnel layer. . The range according to the film thickness ratio is as follows:
Depending on the thickness and the material of the reference D1, the optimum location may be different in the range of the film thickness ratio.

When the tunnel layer 1 and the tunnel layer 2 are basically made of different materials and when effects such as co-tunneling and Cron blockade are included, the element resistance of the TMR element including only the tunnel layer 1 is reduced. Is R1, and the element resistance of the configuration of the present invention including the tunnel layer 1 and the tunnel layer 2 is R2. When R2 ≦ R1 ≦ 10 ⁸ × R2, the output is improved.

Example 4 The following samples were produced on a Si / SiO ₂ substrate by using multi-source sputtering.

Sample 1 Ta (3) / Cu (50) / Ta (3) / Fe (2) / AlO (1.0) / CoFe (3) / Ru (0.9) /
CoFe (3) / PtMn (20) / Ta (25) Samples 2-7 Ta (3) / Cu (50) / Ta (3) / AlO (1.3) / Fe (L) / AlO (1.0) / CoFe
(3) / Ru (0.9) / CoFe (3) / PtMn (20) / Ta (25) (unit: nm)
Here, L is 0.5 to 200 nm. Each sample is heat-treated in a magnetic field of 5 kOe at 280 ° C., then mesa-processed, and Cu (50) / Ta (3) is formed as an upper electrode. Was measured for bias dependence.
The maximum outputs P2 of the samples 2 to 7 were compared with the maximum output P1 of the sample 1 as a reference. The results are shown in (Table 3).

[0102]

[Table 3]

The sharp decrease in P2 / P1 when L is 0.5 nm is considered to be because Fe was not produced as a continuous film. Also, L
Decrease at 200 increases the distance between the two tunnel layers,
This is probably due to the sudden decrease in the number of ballistically conducting electrons. As described above, tunnel layer 1
If the shortest distance between the tunnel layer 2 and L is 1 ≦ L ≦ 100
(Nm), high output can be realized.

Example 5 The following samples were prepared on a Si / SiO ₂ substrate by using multi-source sputtering.

Sample 1 Ta (3) / Cu (50) / Ta (3) / Fe (2) / AlO (1.0) / CoFe (3) / Ru (0.9) /
CoFe (3) / PtMn (20) / Ta (25) Sample 2 Ta (3) / Cu (50) / Ta (3) / AlO (1.3) / PtMn (20) / CoFe (3) / Ru (0.
9) / CoFe (3) / AlO (1.0) / Fe (2) / AlO (1.0) / CoFe (3) / Ru (0.
9) / CoFe (3) / PtMn (20) / Ta (25) Sample 3 Ta (3) / Cu (50) / Ta (3) / AlO (1.3) / Fe (2) / AlO (1.0) / CoFe (3)
/Ru(0.9)/CoFe(3)/PtMn(20)/CoFe(3)/Ru(0.9)/CoFe(3)
/AlO(1.0)/Fe(2)/Ta(25) Sample 4 Ta (3) / Cu (50) / Ta (3) / AlO (1.3) / Fe (2) / AlO (1.0) / CoFe (3 )
/Ru(0.9)/CoFe(3)/PtMn(20)/CoFe(3)/Ru(0.9)/CoFe(3)
/AlO(1.0)/Fe(2)/AlO(1.3)/Ta(25) Sample 5 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe (3) / Ru (0.9 ) / CoFe
(3) / AlO (1.0) / Fe (2) / AlO (1.3) / Fe (2) / AlO (1.0) / CoFe (3)
/Ru(0.9)/CoFe(3)/PtMn(20)/Ta(25) (unit: nm) Here, Sample 2 is FIG. 4, Sample 3 is FIG. 5, Sample 4 is FIG. 6, and Sample 5 is FIG. 7 corresponds to one mode shown in FIG. After heat-treating each sample at 280 ° C. in a 5 KOe magnetic field, mesa processing was performed to form Cu (50) / Ta (3) as an upper electrode, and then the bias dependence of the change in magnetoresistance (MR) was measured. The maximum output P1 that can be taken by sample 1 and sample 2
Comparison of the maximum output P2 that can be taken by 取 り 5 was performed.

[0106]

[Table 4]

As a result, at least one conductive layer,
Two tunnel layers and at least two magnetic layers are stacked, at least one of the tunnel layers is sandwiched between the two magnetic layers, and the resistance changes due to a change in the relative magnetization angle of the two magnetic layers. It can be seen that a high output can be obtained by using a magnetic device that is a resistance layer and is characterized by at least one of the tunnel layers being a tunnel layer that does not depend on a change in the relative magnetization angle.

Example 6 The following samples were produced on a Si / SiO ₂ substrate by using multi-source sputtering.

Sample 1 Ta (3) / Cu (50) / AlO (1.6) / Fe (50) / AlO (1.2) / CoFe (3) / Ru
(0.9) / CoFe (3) / PtMn (20) / Ta (3) / Cu (50) / Ta (3) Sample 2 Ta (3) / Cu (50) / Fe (50) / AlO (1.6) / Fe (50) / AlO (1.2) / CoFe
(3) / Ru (0.9) / CoFe (3) / PtMn (20) / Ta (3) / Cu (50) / Ta (3) Sample 3 Ta (3) / Cu (50) / AlO (1.2) / Fe (50) / AlO (1.6) / CoFe (3) / Ru
(0.9) / CoFe (3) / PtMn (20) / Ta (3) / Cu (50) / Ta (3) Sample 4 Ta (3) / Cu (50) / Fe (50) / AlO (1.2) / Fe (50) / AlO (1.6) / CoFe
(3) / Ru (0.9) / CoFe (3) / PtMn (20) / Ta (3) / Cu (50) / Ta (3)
(Unit: nm) In sample 1, according to the configuration of FIG. 8, Ta (3) / Cu (50) is an emitter electrode, Fe (50) is a base electrode, CoFe (3) / Ru (0.9) / CoFe.
(3) / PtMn (20) / Ta (3) / Cu (50) / Ta (3) was used as the collector electrode.

Sample 2 has a structure of Ta (3) /
Cu (50) / Fe (50) as the emitter electrode, Fe (50) as the base electrode,
CoFe (3) / Ru (0.9) / CoFe (3) / PtMn (20) / Ta (3) / Cu (50) / Ta
(3) was used as a collector electrode. Sample 3 has a collector electrode of Ta (3) / Cu (50), a base electrode of Fe (50), CoFe (3) / Ru (0.9) / CoFe (3) / PtMn according to the configuration of FIG. (20) / Ta (3) / C
u (50) / Ta (3) was used as the emitter electrode. Sample 4 has a collector electrode of Ta (3) / Cu (50) / Fe (50), a base electrode of Fe (50), CoFe (3) / Ru (0.9) / CoFe according to the configuration of FIG. (3) / Pt
Mn (20) / Ta (3) / Cu (50) / Ta (3) was used as the emitter electrode.

Each of the manufactured three-terminal devices was subjected to 280 ° C.
eHeat treatment in a magnetic field. An external magnetic field is applied to Fe (5
0) and the current ratio of the collector current when the magnetization relative angle of CoFe (50) is parallel or antiparallel.
It was changed to 3.5V and examined.

[0112]

[Table 5]

As shown in Table 5, the voltage range in which the collector current changes due to the parallel / antiparallel magnetization is about 300 mV to 3 V, and a high current ratio can be obtained from 500 mV to 2 V.

From the above results, at least one conductive layer, two tunnel layers and at least two magnetic layers are stacked, at least one of the tunnel layers is sandwiched between the two magnetic layers, and the two magnetic layers are stacked. A magnetic device characterized by being a tunnel magnetoresistive layer whose resistance changes with a change in the relative magnetization angle of the layer, and at least one of the tunnel layers is a tunnel layer that does not depend on a change in the relative magnetization angle. This shows that a high output can be obtained.

These devices are composed of at least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2 in the order of, for example, samples 1 and 2 of this embodiment. A magnetic device in which the layer 1 and the magnetic layer 2 have different coercive forces, and the conductive layer 1 is an emitter, the magnetic layer 1 is a base, and the magnetic layer 2 is a collector, or a sample 3 and a sample of the present embodiment. As shown in FIG. 4, at least the conductive layer 1, the tunnel layer 1, the magnetic layer 1, the tunnel layer 2, and the magnetic layer 2 are formed in this order, and the magnetic layers 1 and 2 have different coercive forces. -Since the magnetic device has the magnetic layer 1 as a base and the magnetic layer 2 as an emitter, a high output can be obtained with a relatively simple configuration.

Here, sample 1 and sample 3
When the conductive layer 1 is a non-magnetic conductor, the element configuration becomes the simplest.
As described above, when the conductive layer 1 is a magnetic conductor and has substantially the same coercive force as the magnetic layer 1, a larger output change can be obtained. Further, as in the present embodiment, the magnetic layer 1 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 2 is a fixed magnetic layer whose magnetization rotation is more difficult than that of the magnetic layer 1, and the fixed magnetic layer has a high retention. A high output change can be obtained by magnetically coupling with a force magnetic material, a laminated ferrimagnetic material or an antiferromagnetic material.

In the structure of this embodiment, Fe (50) is replaced with AlO (1.
6) The same tendency as in the present example could be observed in a device in which Fe (20) / Cu (30) was used with Cu as the side.

Example 7 The following samples were produced on a Si / SiO ₂ substrate by using multi-source sputtering.

Samples 1 to 5 Ta (3) / Cu (50) / AlO (d) / NiFe (40) / Fe3Pt (10) / AlO (0.8) / Fe
3Pt (2) / CoFe (1) / Ru (0.9) / CoFe (3) / PtMn (20) / Ta (3) / Cu (5
0) / Ta (3) (unit: nm) Here, Samples 1 to 5 change d from 0.8 to 2.5 nm, and according to the configuration of FIG. 8, Ta (3) / Cu (50 )
Is the emitter electrode, NiFe (40) / Fe3Pt (10) is the base electrode, Fe
3Pt (2) / CoFe (1) / Ru (0.9) / CoFe (3) / PtMn (20) / Ta (25) was used as the collector electrode.

Each of the fabricated three-terminal elements was subjected to 280 ° C.
eHeat treatment in a magnetic field. The collector current was measured when an external magnetic field was applied and the relative magnetization angles of Fe (50) and CoFe (50) sandwiching AlO (0.8) were made parallel. Here, the emitter voltage was 1 V. The relative current gain based on the value when Re / Rc is 1 is shown in (Table 6). Re / Rc is the base /
Rc is the resistance at a low bias between the collectors, and Re is the resistance at a low bias between the base and emitter.

[0121]

[Table 6]

[0122] current gain when Re / Rc is less than 1 is small, also 10 ⁸ time greater than could not be measured due to noise. From the above results, it can be seen that a high current gain is obtained when Rc ≦ Re ≦ 10 ⁸ × Rc.

Example 8 The following samples were prepared on a Si / SiO ₂ substrate by using multi-source sputtering.

Samples 1 to 6 Ta (3) / Cu (50) / AlO (1.6) / CoFe (L) / AlO (1.2) / CoFe (3) / Ru
(0.9) / CoFe (3) / PtMn (20) / Ta (3) / Cu (50) / Ta (3) (unit: nm) where L is 0.5 to 200 nm Each sample has the structure shown in FIG. Correspondingly, Ta (3) / Cu (50)
Is the emitter electrode, CoFe (L) is the base electrode, CoFe (3) / Ru (0.
9) / CoFe (3) / PtMn (20) / Ta (3) / Cu (50) / Ta (3) is used as the collector electrode. After heat treatment at 280 ° C and 5 kOe magnetic field, A
The collector current was investigated when the relative magnetization angles of Fe (50) and CoFe (50) sandwiching lO (1.2) were parallel. Where the emitter voltage is
1V. The relative current gain based on the current gain when L is 50 nm is shown in (Table 7).

[0125]

[Table 7]

The sharp decrease of the current gain when L is 0.5 nm is due to Co
This is probably because Fe was not produced as a continuous film. Further, it is considered that the decrease when L is 200 is due to the fact that the distance between the two tunnel layers is widened and the number of ballistically conducting electrons is rapidly reduced.

As described above, assuming that the shortest distance between the tunnel layers 1 and 2 is L, high output can be realized when 1 ≦ L ≦ 100 (nm).

(Example 9) The following samples were produced on an n-GaAs (100) substrate by using multiple sputtering.

Sample 1 GaAs / Fe (10) / AlO (1.6) / CoFe (3) / Ru (0.9) / CoFe (3) / IrMn
(20) / Ta (3) / Cu (50) / Ta (3) Sample 2 GaAs / Au (8) / Fe (2) / AlO (1.6) / CoFe (3) / Ru (0.9) / CoFe (3 ) /
IrMn (20) / Ta (3) / Cu (50) / Ta (3) Sample 3 GaAs / Au (8) / Fe (2) / AlO (1.6) / CoFe (3) / Ta (3) / Cu ( 50) / Ta
(3) (unit: nm) The multilayer film is formed in a magnetic field of 100 Oe to form a uniaxial anisotropy in IrMn.

Sample 1 was made of CoFe according to the configuration of FIG.
(3) / Ru (0.9) / CoFe (3) / IrMn (20) / Ta (3) / Cu (50) / Ta (3) as emitter electrode, Fe (10) as base electrode, n-GaAs The (100) substrate was used as a collector electrode. Sample 2 has a structure of CoFe (3) / Ru (0.9) / CoFe (3) / IrMn (20) / Ta (3) / Cu (5
0) / Ta (3) as emitter electrode, Au (8) / Fe (2) as base electrode, n
-A GaAs (100) substrate was used as a collector electrode. Sample 3
Represents CoFe (3) / Ta (3) / Cu (50) / Ta (3) according to the configuration of FIG.
Is an emitter electrode, Au (8) / Fe (2) is a base electrode, n-GaAs (10
0) The substrate was used as a collector electrode.

An external magnetic field is applied to each of the fabricated three-terminal devices, and the current ratio of the collector current when the relative magnetization angles of Fe and CoFe (3) sandwiching AlO (1.6) are made parallel or antiparallel is expressed by the emitter voltage. Was changed from 0 V to 3.5 V and examined.

[0132]

[Table 8]

As shown in Table 8, the voltage range in which the collector current changes due to the parallel / antiparallel magnetization is about 300 mV to 3 V, and a high current ratio can be obtained from 500 mV to 2 V. The reason why the current ratio is slightly higher in Sample 2 than in Sample 1 is probably because a good shot-junction was formed at the n-GaAs / Au interface.

In this example, a GaAs substrate was used to enhance the crystallinity of Au and Fe, but the substrate used was n-Si
And so on.

As described above, at least the magnetic layer 1, the tunnel layer 1, the magnetic layer 2, and the semiconductor 1 are formed in this order. The magnetic layer 1 and the magnetic layer 2 have different coercive forces, and the magnetic layer 1 A magnetic device having a magnetic layer 2 as a base and a semiconductor as a collector, or a high output change is obtained by interposing the conductive layer 1 at least between the magnetic layer 2 and the semiconductor in the above configuration. be able to.

The magnetic layer 2 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 1 is a fixed magnetic layer whose magnetization rotation is more difficult than that of the magnetic layer 2, and the fixed magnetic layer is a high coercivity magnetic material. High output can be obtained by magnetically coupling with a ferrimagnetic material or an antiferromagnetic material.

Example 10 An integrated memory was fabricated on a CMOS substrate using a memory element having a basic configuration as shown in FIG. The element arrangement was a total of 8 blocks, with a memory of 16 × 16 elements as one block. Here, the elements shown in FIG.
(a) Sample 1 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe (3) / Ru (0.9) / CoFe
(3) / AlO (1.0) / NiFe (2) / AlO (1.3) / Ta (25) (unit: nm)
Was used.

As a comparative example, a sample 2 Ta (3) / Cu (50) / Ta (3) / PtMn (20) / CoFe (3) / Ru (0.9) / CoFe
(3) / AlO (1.0) / NiFe (2) / Ta (25) was used.

The element cross-sectional area of each sample was 0.2 μm
FIG. 18A shows the in-plane shape of NiFe (2) which is × 0.3 μm and is a free magnetic layer.

The remaining one element of each part lock is a dummy element for canceling wiring resistance, element minimum resistance, and FET resistance. Note that Cu was used for all word lines and bit lines.

By the combined magnetic field of the word line and the bit line, 8
The magnetization reversal of each magnetic layer 1 was simultaneously performed on eight elements of one block, and a signal of eight bits was recorded. Next, a gate of an FET made of CMOS was turned on one element at a time in each block, and a sense current was passed. At this time, the voltage generated in the bit line, element, and FET in each block was compared with the dummy voltage by a comparator, and 8-bit information was simultaneously read from the output voltage of each element. The output was about twice that in the case of using the TMR element of the comparative example.

Next, in the film configuration of Sample 2,
The ratio of the major axis to the minor axis of the free magnetic layer is 1.5: 1 (the major axis is 0.2 μm)
Then, an integrated memory whose shape was changed to that shown in FIGS. The power consumption required for recording these memories is
In the shapes of (2) to (5) in FIG. 18, the shape of FIG.
It was about 1/2.

[0143]

By using, for example, the simplest configuration of the magnetic device of the present invention, it is possible to obtain a magnetoresistance effect higher than that of a conventional TMR element having a single tunnel layer, and to obtain a conventional ferromagnetic device. The layer thickness can be made thinner than a heavy tunnel element. As a result, it is possible to achieve the required high output in accordance with the miniaturization of the device, and also, for example, when used for a HDD reproducing head, a narrow gap required for a high recording density, or when used as a memory element, a current This has the effect of lowering the magnetic field (lower power consumption).

Further, in the magnetic device having the three-terminal structure of the present invention, a high current gain and a high current change ratio with respect to external magnetic energy can be realized.

By using these devices, a reproducing head of a magnetic recording apparatus such as a magneto-optical disk, a hard disk, a digital data streamer (DDS), or a digital VTR used for a conventional information communication terminal or the like is used. A magnetic sensor for detecting the rotational speed of a cylinder or an automobile, a magnetic random access memory (MRAM), a stress or acceleration sensor for detecting a change in stress or a change in acceleration, or a heat sensor or a chemical reaction sensor And the like can be improved.

An object of the present invention is to provide a magnetic device having a relatively small layer thickness and a high output or a high current gain, which addresses such a conventional problem.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration example of a magnetic device of the present invention.

FIG. 2 is a diagram showing a configuration example of a magnetic device of the present invention.

FIG. 3 is a diagram showing an example of manufacturing a magnetic device of the present invention.

FIG. 4 is a diagram showing a configuration example of a magnetic device of the present invention.

FIG. 5 is a diagram showing a configuration example of a magnetic device of the present invention.

FIG. 6 is a diagram showing a configuration example of a magnetic device of the present invention.

FIG. 7 is a diagram showing a configuration example of a magnetic device according to the present invention.

FIG. 8 is a diagram showing a configuration example of a magnetic device according to the present invention.

FIG. 9 is a diagram showing a configuration example of a magnetic device according to the present invention.

FIG. 10 is a diagram showing a configuration example of a magnetic device according to the present invention.

FIG. 11 is a diagram showing a configuration example of a magnetic device according to the present invention.

FIG. 12 is a diagram showing a configuration example of a magnetic device of the present invention.

FIG. 13 is a diagram showing a configuration example of a magnetic device of the present invention.

FIG. 14 is a diagram showing an example of a random access memory;

FIG. 15 is a diagram showing a memory configuration 1;

FIG. 16 is a diagram showing a memory configuration 2;

FIG. 17 is a diagram showing a memory configuration 3;

FIG. 18 is a view showing an in-plane shape of a free magnetic layer.

FIG. 19 is a diagram showing the bias dependence of Sample 1.

FIG. 20 is a view showing the bias dependence of Sample 3.

FIG. 21 is a diagram showing bias dependence of Sample 5.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 27/105 H01L 27/10 447 (72) Inventor Yasunari Sugita 1006 Kazuma, Kazuma, Kazuma, Osaka Matsushita Electric Industrial (72) Inventor Mitsuo Satomi 1006 Kadoma, Kadoma, Osaka Pref.Matsushita Electric Industrial Co., Ltd. (72) Inventor Yoshio Kawashima 1006 Odaka, Kadoma, Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. (72) Inventor Akihiro Odagawa 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture F-term (reference) 2G017 AA01 AB07 AD55 AD65 5D034 BA03 BA04 BA08 BA15 CA00 CA08 5F083 FZ10 GA05 GA11 GA30 JA36 JA37 JA38 JA39 JA40 JA60 PR03 PR21 PR40

Claims (25)

[Claims] 1. At least one conductive layer, two tunnel layers and at least two magnetic layers are stacked, and at least one of the tunnel layers is sandwiched between two magnetic layers;
And a tunnel magnetoresistive layer whose resistance changes according to a change in the relative magnetization angle of the two magnetic layers, and at least one of the tunnel layers is a tunnel layer that does not depend on a change in the relative magnetization angle. And a magnetic device. 2. A magnetic layer comprising at least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2, wherein the magnetic layer 1 and the magnetic layer 2 have different coercive forces. The magnetic device according to claim 1, wherein a change in the relative magnetization angle between the magnetic layer and the magnetic layer is detected as at least a change in resistance between the conductive layer and the magnetic layer. 3. The magnetic device according to claim 2, wherein the conductive layer 1 is a non-magnetic conductor. 4. The magnetic device according to claim 2, wherein the conductive layer is a magnetic conductor and has substantially the same coercive force as the magnetic layer. 5. The magnetic layer 1 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 2 is a fixed magnetic layer whose magnetization rotation is more difficult than that of the magnetic layer 1, and the fixed magnetic layer has a high coercivity. body,
The magnetic device according to claim 2, wherein the magnetic device is magnetically coupled to a laminated ferrimagnetic material or an antiferromagnetic material. 6. The magnetic device according to claim 2, wherein the resistance of the tunnel layer 1 is R1 and the resistance of the tunnel layer 2 is R2. 0.5 × R2 ≦ R1 ≦ 100 × R2 Magneto-resistive devices that are in the range. 7. The magnetic device according to claim 2, wherein the tunnel layer 1 and the tunnel layer 2 are formed of the same material, the thickness of the tunnel layer 1 is D1, and the tunnel layer 2 is Is a range of 0.9 × R2 ≦ R1 ≦ 1.5 × R2, where D2 is a film thickness of D2. 8. The magnetoresistive device according to claim 6, wherein the shortest distance between the tunnel layer 1 and the tunnel layer 2 is in the range of 1 ≦ L ≦ 100 (nm). 9. At least the magnetic layer 1, the tunnel layer 1, the magnetic layer 2, the tunnel layer 2, the magnetic layer 3, the tunnel layer 3, and the magnetic layer 4 in this order. Are free magnetic layers (pinned magnetic layers), the magnetic layers 2 and 3 are pinned magnetic layers (free magnetic layers), between the magnetic layer 1 and the magnetic layer 2, and between the magnetic layers 2 and 3. The magnetic device according to claim 1, wherein a change in the relative magnetization angle between the magnetic layer and the magnetic layer is detected as a resistance change between at least the magnetic layer and the magnetic layer. 10. At least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2 are formed in this order, and the magnetic layer 1 and the magnetic layer 2 have different coercive forces,
2. The magnetic device according to claim 1, wherein the conductive layer 1 is an emitter, the magnetic layer 1 is a base, and the magnetic layer 2 is a collector. 11. At least a conductive layer 1, a tunnel layer 1, a magnetic layer 1, a tunnel layer 2, and a magnetic layer 2 are arranged in this order, and the magnetic layer 1 and the magnetic layer 2 have different coercive forces,
2. The magnetic device according to claim 1, wherein the conductive layer 1 is a collector, the magnetic layer 1 is a base, and the magnetic layer 2 is an emitter. 12. The magnetic device according to claim 10, wherein the conductive layer 1 is a non-magnetic conductor or a magnetic conductor. 13. The conductive layer 1 is a magnetic conductor and the magnetic layer 1
The magnetic device according to any one of claims 10 to 12, which has substantially the same holding force as described above. 14. The magnetic layer 1 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 2 is a fixed magnetic layer whose magnetization rotation is more difficult than that of the magnetic layer 1, and the fixed magnetic layer has a high coercivity. body,
14. The magnetic device according to claim 10, wherein the magnetic device is magnetically coupled to a laminated ferrimagnetic material or an antiferromagnetic material. 15. A magnetic device according to any one of claims 10 14, the emitter side of the resistance Re of the tunnel layer, the collector side of the resistance of the tunnel layer and Rc Rc ≦ Re ≦ 10 ⁸ × A magnetoresistive device in the range of Rc. 16. The magnetoresistive device according to claim 15, wherein the shortest distance between the tunnel layer 1 and the tunnel layer 2 is in a range of 1 ≦ L ≦ 100 (nm). 17. At least a magnetic layer 1, a tunnel layer 1, a magnetic layer 2, and a semiconductor 1 in this order. The magnetic layer 1 and the magnetic layer 2 have different coercive forces, and the magnetic layer 1 is an emitter, A magnetic device having the magnetic layer 2 as a base and the semiconductor 1 as a collector. 18. The magnetic device according to claim 17, wherein the conductive layer 1 is interposed at least between the magnetic layer 2 and the semiconductor. 19. The magnetic layer 2 is a free magnetic layer whose magnetization rotation is easy, the magnetic layer 1 is a fixed magnetic layer whose magnetization rotation is more difficult than the magnetic layer 2, and the fixed magnetic layer has a high coercivity. body,
19. The magnetic device according to claim 17, wherein the magnetic device is magnetically coupled to a laminated ferrimagnetic material or an antiferromagnetic material. 20. The magnetic device according to claim 1, wherein the tunnel layer is an oxide, nitride or oxynitride of Al. 21. The magnetic device according to claim 1, wherein a bias applied to at least one tunnel layer is not less than 300 mV and not more than 3 V. 22. The magnetoresistive device according to claim 6, wherein the tunnel layer is an oxide, nitride or oxynitride of Al. 23. The magnetoresistive device according to claim 6, wherein a bias applied to at least one tunnel layer is not less than 300 mV and not more than 3 V. 24. A magnetic memory using the magnetoresistive device according to any one of claims 6, 7, 8, 15, and 16. 25. A memory device using the magnetoresistive device according to any one of claims 6, 7, 8, 15, and 16.